The invention relates to a force measuring apparatus in the form of a force-transmitting component having a strain measuring element which is held on the component and which converts the force-dependent strain of the component into an electric signal. Furthermore, the invention relates to a strain measuring element which registers the force-dependent strain of a component.
A tensile force sensor is disclosed by DE 41 03 765 A1. A link plate which has an eye at each of its two longitudinal ends is provided with a cylindrical depression from two sides in the region between the eyes. Adhesively bonded to the base of the depressions is a strain gage serving as a strain measuring element. The link plate is, for example, inserted into the force flow of a crane transporting a load. In this case, the link plate is deformed in accordance with the force with which it is loaded. The deformation of the link plate in the same way deforms the strain gage adhesively bonded to the base of the depression. In the process, the electric output signal from the strain gage changes in accordance with the deformation of the strain gage.
The known force sensor is provided in order to measure forces in rough crane or ship operation up to an order of magnitude of several hundred tons. If, by contrast, smaller forces are to be measured, the deformation of the link plate as a function of the loading is too small to obtain a usable electric output signal from the strain gage.
The invention is based on the object, in a force measuring apparatus of the type mentioned at the beginning, of improving the resolution, that is to say in particular of obtaining a larger electric output signal with the same deformation of the force-transmitting component.